Coat a large nonstick skillet with cooking spray and heat over medium-high heat. Crumble in the beef and cook, stirring often, until it loses its pink color, about 5 minutes. Drain the beef in a colander and wipe out the skillet.
In the same skillet, heat the oil over medium heat. Add the bell pepper and cook, stirring often, until tender, about 3 minutes.
Return the beef to the skillet and stir in the tomato sauce, corn, ketchup, vinegar, sugar, and black pepper. Bring just to a boil.
Reduce the heat and simmer until slightly thickened, about 10 minutes.
Serve on whole-wheat hamburger buns with add-ons like chopped onion, pickled peppers, pickle slices, low-fat grated cheese, tomato slices, or whatever other toppings you like.